A team of European Union negotiators arrive Sunday to conduct talks with British representatives in Brussels on Britain's exit from the EU. Photo by Olivier Hoslet/EPA-EFE

Oct. 15 (UPI) -- Weekend negotiations regarding Britain's withdrawal from the European Union broke down, days before a crucial summit meeting on Brexit.

The most significant issue is over the border between Ireland, an EU member, and Northern Ireland, which is part of the United Kingdom planning to leave the union. The EU seeks an open border and single European market between the two countries, which is Britain's fallback or "backstop" position.

Dominc Raab, Britain's lead negotiator, met with EU counterpart Michel Barnier in Brussels on Sunday, and later announced an impasse. A joint statement from the British prime minister's office and the Department for Exiting the European Union referred to the Ireland issue as sticking point.

"In the last few days U.K. and EU negotiators have made real progress in a number of key areas. However, there remain a number of unresolved issues relating to the backstop," it read.

Planned talks this week in Luxembourg are on hold and no additional negotiations are planned. Britain is scheduled to leave the EU in March, and the Bank of England has warned that economic chaos will follow if the sides fail to reach a deal.

We met today @DominicRaab and UK negotiating team. Despite intense efforts, some key issues are still open, including the backstop for IE/NI to avoid a hard border. I will debrief the EU27 and @Europarl_EN on the #Brexit negotiations.

Keeping an open border between Northern Ireland and the Republic of Ireland could force the rebuilding of customs and law enforcement posts. The permanent removal of border infrastructure was an element of the 1998 Good Friday Agreement, which brought peace to Ireland after decades of sectarian conflict.

The EU has suggested that Northern Ireland should follow European regulations on customs protocols for goods and services after Britain leaves. The result would be two separate customs zones for Britain, which British Prime Minister Theresa May has rejected.

Any sign of compromise could hurt her Conservative Party politically in Britain. Her counter-proposal, in which all of Britain would remain in the EU's customs sphere, was rejected by the EU.

"Given the way in which the EU has behaved and the corner they've put Theresa May into, there's no deal which I can see at present which will command a majority in the House of Commons. So it is probably inevitable that we will end up with a no deal scenario," Sammy Wilson, Brexit spokesman of the minority Democratic Unionist Party, said on Sunday. "I think that anybody looking at it objectively would say that what is on offer from the EU is a far worse deal than a no deal, and therefore she'd be mad to be railroaded into accepting it."